Direct answer
Expand access one area at a time after a reliable period with supervision. If accidents return, reduce the area and increase scheduled trips instead of treating the change as defiance.
Start smaller than feels necessary
Beginning with just one or two rooms you can consistently supervise makes it much easier to catch signals early and prevent accidents before they happen.
Let reliability set the pace
Some trainers use an extended accident-free stretch, often framed around several consecutive weeks, before opening up more of the house. The exact number matters less than the underlying idea: expand access based on demonstrated reliability, not a calendar date.
Expect to step back sometimes
If accidents start increasing after you expand access, it is reasonable to shrink the space again for a while rather than treat it as a permanent failure.
What to avoid
Keep the response gentle.
Avoid giving full run of the house early "to see how it goes" — it removes the supervision that makes learning possible.
Safety boundary
When to get more help.
This applies to healthy dogs learning a routine. A sudden need to shrink access again after a long reliable stretch is worth mentioning to your veterinarian.
References
Evidence and professional guidance
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